T4 - Waves

Question 1

Amplitude (A) - wave

Answer 1

Maximum displacement of the medium from the equilibrium position

Question 2

Amplitude (A) - SHM

Answer 2

Maximum displacement from the equilibrium position

Question 3

Simple harmonic motion (SHM)

Answer 3

an oscillation where the force (and acceleration) is proportional to displacement from the equilibrium position but is in the opposite direction

Question 4

analyser

Answer 4

a device that can detect polarised light

Question 5

antinode

Answer 5

position of maximum displacement

Question 6

Brewster’s law

Answer 6

when light reflects off a surface it will be 100% polarised in the plane of the surface if the angle between the reflected and refracted rays is 90 degrees

Question 7

coherent

Answer 7

wave sources that have a fixed phase relationship

Question 8

compression

Answer 8

part of a longitudinal wave where the particles are closest together

Question 9

constructive interference

Answer 9

occurs when two wave meet in phase to give the maximum displacement

Question 10

critical angle (θc)

Answer 10

angle of incidence above which total internal reflection may occur

Question 11

destructive interference

Answer 11

curse when two waves meet out of phase to give zero displacement

Question 12

diffraction

Answer 12

spreading out of eaves past an obstacle or through a gap

Question 13

displacement (X) - SHM

Answer 13

instantaneous distance from the equilibrium position in a specific direction

Question 14

displacement (X) - wave

Answer 14

instantaneous distance the medium has moved from the equilibrium position in a specific direction

Question 15

electromagnetic wave

Answer 15

do not require a medium so can travel through a vacuum

Question 16

frequency (f) - SHM

Answer 16

number of oscillations per second

Question 17

frequency (f) - wave

Answer 17

number of oscillation of the medium per second

Question 18

fundamental frequency (fo)

Answer 18

the lowest frequency standing waves that can be formed a pipe or a string

Question 19

intensity (I)

Answer 19

power per unite area received by an observer

Question 20

isochronous oscillation

Answer 20

an oscillation with a constant time period

Question 21

longitudinal wave

Answer 21

the particles of the medium oscillate parallel to the direction of energy transfer

Question 22

Malus’ law

Answer 22

I = Io cos^2 θ

Question 23

mechanical waves

Answer 23

requires a medium through which to travel

Question 24

node

Answer 24

position of fire displacement

Question 25

optically active substance

Answer 25

substance that rotates the plane of polarised light as the light passes through it

Question 26

path difference

Answer 26

difference in distance travelled by two different waves, given in terms of wavelength

Question 27

period (T) - SHM

Answer 27

time for one oscillation

Question 28

period (T) - waves

Answer 28

time for one complete oscillation of the medium (or for a complete wave to pass a given point )

Question 29

polarised light

Answer 29

light in which the electric field vector is oscillating on one plane only

Question 30

rarefaction

Answer 30

part of a longitudinal wave where the particles are furthest apart

Question 31

ray

Answer 31

shows the direction of energy transfer of a wave

Question 32

refraction

Answer 32

the chance in speed of a wave that occurs when it travels into a different medium

Question 33

refractive index (n)

Answer 33

a measure of how fast a wave travels in medium

Question 34

retiring force - SHM

Answer 34

a force that is always directed towards the equilibrium position

Question 35

Snell’s law

Answer 35

n = sin i / sin r

Question 36

standing wave

Answer 36

a wave formed when a wave is reflected and the reflected wave interferes with the forward moving wave

Question 37

superposition

Answer 37

a resultant wave formed by the addition of the displacement of individual aves when the interfere

Question 38

total internal reflection

Answer 38

occurs when a wave is travelling into a less dense medium and when the angle of incidence at the boundary is greater that the critical angle

Question 39

transverse waves

Answer 39

the particles of the medium oscillate perpendicular to the direction of energy transfer

Question 40

wave

Answer 40

a movement of energy through a medium

Question 41

wave speed (c)

Answer 41

distance travelled per unit time by the energy of wave

Question 42

wavefront

Answer 42

Lin connecting points along a ave that are in phase

Question 43

wavelength (λ)

Answer 43

shortest distance along a wave between two points that are in phase